This is a simple trick or better – simple test you can do to test if your wetsuit has good stitches. These day wetsuits from medium qualitymodels and up should have 100% waterproof seams. If they don’t, keep your hands off.
Stitches themselves can never be completely waterproof. Even if the wetsuit is made using blind stitch technology, where the needle does not penetrate the neoprene, there are still some holes that let the water in. So a few years back liquid taping, liquid seal (or any other liquid sometinhg name you can find) became the name of the game. Liquid seal is a liquid rubbery material that is used to seal the stitches, making them 100% waterproof.
Liquid Seal / Liquid Taping… looks something like this:
Now the picture would be a little better if we had three arms and one of them could hold the camera :).